The present invention relates to continuity testers more particularly to gun-type probes for checking the possibility of open circuits in wires in vehicles, buildings and other field installations and also in original electrical equipment, incident to manufacture and repair thereof.
The state of the art in such devices is represented by U.S. Pat. No. 3,363,171 granted Jan. 9, 1968 to Vernon H. Sietmann and Robert A. Louks and U.S. Pat. No. 3,768,005 granted Oct. 23, 1973 to Robert A. Louks and U.S. and foreign patents cited in both the above-enumerated patents. Such devices comprise a hand held implement resembling a pistol or hypodermic needle with an elongated barrel carried on a hand grip and barrel support body, the barrel containing a pierce probe with a forward end and with the barrel terminating at its forward end in a grappling hook defining a region in which a wire to be tested may be secured while the pierce probe is advanced forward to pierce the insulation of the wire and establish a contact between the wire and a pointed conductive forward end of the pierce probe. Such conductive contact is part of a complete circuit running through the length of the pierce probe to a signal of circuit completion, such as a light bulb or a buzzer, and also comprising an alligator clamp contained on the end of an extension wire extending from a device, which may be clipped to a portion of a circuit which includes the wire to be tested. Such devices also may be used for testing of terminals by establishing an external conductive portion, such as a conductive needle extension or a conductive body portion, without use of the grappling hook portion to grasp a wire.
It is an important object of the present invention to provide a reliable, consistently effective continuity tester of the class described.
It is a further object of the invention to provide the capability of testing the continuity of electrical wires and other conductors, apart from any circuit context consistent with the preceding object.
It is a further object of the present invention to provide economy and ease of manufacture consistent with one or both of the preceding objects.
It is a further object of the invention to provide a probe locking capability in devices of the class described consistent with one or more of the preceding objects.
It is a further object of the invention to provide ease of consumable parts replacement, consistent with one or more of the preceding objects.
It is a further object of the invention to provide terminal testing capability without reference to probe position in devices of the class described, consistent with one or more of the preceding objects.
It is a further object of the invention to provide a geometric envelope for the device which, in each of its three dimensions, it is not too large and not too small consistent with the device usage context, consistent with one or more of the preceding objects.